YEAR	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec	Annual 24-hr Avg.
1990	17106	18459	18608	18818	17204	18048	17541	18096	18179	18276	17940	15384	17795
1991	16436	18045	17458	19514	17741	18667	18107
1992		16220	17650	18807	17075	18429	18723	18869	18956	19146	18164	17544
1993	17384	19444	19756	21187	19438	20247	19085	18918	21571	20943	19881	19023	19731
1994	18778	21054	21878	22033	20512	20908	19241	20472	22413	21901	21240	19541	20820
1995	20038	22193	22199	23155	21461	21867	19964	21305	23048	22915	21377	19841	21614
1996	20093	22267	21864	23320	20556	20313	19072	20715	22725	21877	21134	17953	20991
1997	18988	21562	21319	23039	21416	20822	19008	20039	22293	21741	20699	18802	20811
1998	18219	20982	20535	21653	20239	20357	18691	20031	21882	21768	20339	18874	20298
1999	20150	20962	20923	22282	21185	20809	20079	20844	22074	22155	20542	18908	20909
2000	19170	21683	21426	22502	20670	20356	19070	20416	22297	22679	20961	19504	20895
2001	19046	21306	21254	22330	19917	19520	18546	19611	20645	20894	19598	17651	20027
2002	17967	19807	19162	21427	19346	18203	17359	18538	20259	20606	19303	18136	19176
2003	18652	20039	19154	20950	19355	21371	18019	18726	21337	21107	18747	18239	19641
2004	18241	20025	20616	21515	19253	18848	17680	18546	21986	20678	19663	18124	19598
2005	18697	20446	20345	21329	19365	18779	17794	19848	20688	20384	19150	17666	19541
2006	18020	20215	19971	20677	19471	18494			21167	20860	19390	17501
2007	18372	20423	20235	20971	19505	18750	17673	19191	20718	21768	19452	17541	19550
2008	17053	19984	19314	21376	19821	17781	17436	18048	20418	20421	17938	17226	18901
2009	16889	19536	18954	20803	18571	17782	17647	18035	20209

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